Flexible multielectrode arrays based electrochemical aptasensor for glycated human serum albumin detection

Abstract

Assessment tests for glycemic control of patients with diabetes mellitus commonly use blood glucose and glycated hemoglobin A1C (HbA1 C) levels for estimating acute and long-term glycemia, respectively. Diabetes diet, as well as treatment, are adapted accordingly and also the risk of diabetic complications can be estimated. Glycated human serum albumin (GHSA) has been proposed as alternative to HbA1C since it possesses a four times shorter lifespan and its blood concentration is not affected by hemic diseases. Here, an electrochemical aptasensor is proposed for the simultaneous detection of human serum albumin (HSA) and GHSA utilizing flexible multielectrode arrays. The polymer chip carries two individual sets of gold electrodes, which are separately modified by the corresponding aptamers. The dual-target aptasensors possessed detection limits as low as 13 nM and 25 nM for HSA and GHSA, respectively, together with detection ranges lasting from 40 nM to 10 µM. Moreover, our aptasensor quantified selectively its target in diluted full-blood samples. This first PoC, low-cost plastic aptasensor facilitates the simultaneous and quantitative determination of HSA and GHSA ratios by analyzing the current signals from several redundant electrodes in the same sample, which permits a reliable and affordable estimation of long-term glycemia at point-of-care or home.